[fortran,patch] Volatile variable in commons and equivalence groups

[FX]

Hi all,

Patch below fixed PR35037, where we used not to mark as volatile the
members of common or equivalence groups. This is straightforward and
well contained, fixes a wrong-code PR, but it's not a regression
AFAIK, so I'm asking it to be reviewed and for the reviewer to
indicate whether it is suitable for inclusion in 4.3.

Bootstrapped and regtested on x86_64-linux, will come with a testcase
(based on -O3 simplification and scanning of the optimized tree dump,
like is done in the PR).

FX




2008-02-05  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>

        PR fortran/35037
        * trans-common.c (build_field): Mark fields as volatile when needed.



Index: trans-common.c
===================================================================
--- trans-common.c      (revision 132112)
+++ trans-common.c      (working copy)
@@ -318,6 +318,15 @@ build_field (segment_info *h, tree union
       GFC_DECL_ASSIGN_ADDR (field) = pushdecl_top_level (addr);
     }

+  /* If this field is volatile, mark it.  */
+  if (h->sym->attr.volatile_)
+    {
+      tree new;
+      TREE_THIS_VOLATILE (field) = 1;
+      new = build_qualified_type (TREE_TYPE (field), TYPE_QUAL_VOLATILE);
+      TREE_TYPE (field) = new;
+    }
+
   h->field = field;
 }



-- 
FX Coudert
http://www.homepages.ucl.ac.uk/~uccafco/